US20150223758A1 - Electrocardiogram sensor and method of processing signals using the same - Google Patents
Electrocardiogram sensor and method of processing signals using the same Download PDFInfo
- Publication number
- US20150223758A1 US20150223758A1 US14/598,918 US201514598918A US2015223758A1 US 20150223758 A1 US20150223758 A1 US 20150223758A1 US 201514598918 A US201514598918 A US 201514598918A US 2015223758 A1 US2015223758 A1 US 2015223758A1
- Authority
- US
- United States
- Prior art keywords
- offset
- ecg signal
- ecg
- value
- digital
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/30—Input circuits therefor
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7203—Signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/0002—Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network
- A61B5/0004—Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network characterised by the type of physiological signal transmitted
- A61B5/0006—ECG or EEG signals
-
- A61B5/04002—
-
- A61B5/04012—
-
- A61B5/0408—
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/2415—Measuring direct current [DC] or slowly varying biopotentials
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/25—Bioelectric electrodes therefor
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/24—Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
- A61B5/316—Modalities, i.e. specific diagnostic methods
Definitions
- At least one example embodiment of the inventive concepts relates to an electrocardiogram (ECG) sensor, and more particularly, to an ECG sensor capable of performing DC offset and gain adjustment at one time and/or a method of processing a signal using the same.
- ECG electrocardiogram
- An ECG sensor is usually used to measure an ECG of a patient's heart.
- the ECG sensor processes and analyzes a signal measured from an electrode directly contacting a patient's body and the patient's physical condition can be evaluated using ECG signals output from the ECG sensor.
- an electrocardiogram (ECG) sensor includes an analog front end device configured to remove a DC offset in a first ECG signal received from a measuring electrode, and adjust a gain amplification value based on the first ECG signal.
- the analog front end device is configured to output an adjusted first ECG signal, the adjusted first ECG signal being based on the adjusted gain amplification value and the removed DC offset in the first ECG signal.
- the ECG sensor includes a digital signal processor configured to analyze and process the adjusted first ECG signal based on an algorithm and to output information.
- the analog front end device is configured to remove the DC offset in the first ECG signal during a first period, and remove a DC offset in a second ECG signal and simultaneously adjust a gain amplification value for the second ECG signal during a second period.
- the analog front end device comprises an amplifier configured to receive the first ECG signal from the measuring electrode and amplify the first ECG signal based on the gain amplification value for the first ECG signal.
- the AFE includes an analog-to-digital converter configured to perform analog-to-digital conversion on the amplified first ECG signal and output a digital ECG signal.
- the AFE includes an automatic gain controller configured to detect a peak value of the digital ECG signal and to adjust the gain amplification value for the adjusted first ECG signal based on the peak value.
- the AFE further comprises a DC offset calculator configured to calculate a mean value of the digital ECG signal, calculate a DC offset with respect to the mean value, and output the DC offset calculated with respect to the mean value.
- the AFE includes a digital-to-analog converter configured to perform digital-to-analog conversion on the DC offset output from the DC offset calculator to output an analog DC offset.
- the amplifier is configured to remove the DC offset from the first ECG signal based on the analog DC offset.
- the DC offset calculator is configured to determine whether the DC offset calculated with respect to the mean value is in a first reference range.
- the DC offset calculator is configured to output a bit value corresponding to a changed DC offset with respect to the digital ECG signal if the DC offset calculated with respect to the mean value is not in the first reference range, the bit value being output to the digital-to-analog converter.
- the automatic gain controller is configured to detect the peak value of the digital ECG signal and to determine whether the detected peak value is in a second reference range.
- the automatic gain controller is configured to output a bit value corresponding to a changed gain amplification value with respect to the digital ECG signal if the detected peak value is not in the second reference range, the bit value being output to the amplifier.
- the automatic gain controller comprises a timer configured to count a time during which the adjusted gain amplification value is applied to one of the first and second ECG signals.
- the ECG sensor includes a radio frequency (RF) module configured to transmit the information detected by the digital signal processor via a wireless connection.
- RF radio frequency
- a method of processing a signal using an electrocardiogram (ECG) sensor includes calculating, by the ECG sensor, a DC offset in an initial ECG signal received from a measuring electrode during a first period.
- the method includes removing, by the ECG sensor, a DC offset from a first ECG signal received during a second period, the removing being based on the calculated DC offset in the initial ECG signal.
- the method includes calculating, by the ECG sensor, a DC offset in a second ECG signal received during the second period and adjusting a gain amplification value for the second ECG signal.
- the calculating the DC offset in the second ECG signal comprises calculating a DC offset with respect to a mean value of the second ECG signal, determining whether the DC offset is in a first reference range, and outputting a bit value corresponding to a decreased or increased DC offset with respect to the second ECG signal if the DC offset is not in the first reference range.
- the adjusting the gain amplification value for the second ECG signal comprises detecting a peak value of the second ECG signal, determining whether the peak value is in a second reference range, and outputting a bit value corresponding to a decreased or increased gain amplification value with respect to the second ECG signal if the peak value is not in the second reference range.
- the calculating the DC offset in the second ECG signal and the adjusting the gain amplification value for the second ECG signal are performed simultaneously and repeatedly while the ECG sensor is operating.
- a device comprises an analog front end device configured to calculate a first DC offset in a first ECG signal received from a measuring electrode, and remove a second DC offset in a second ECG signal based on the calculated first DC offset.
- the second ECG signal may be received subsequent to the first ECG signal.
- the analog front end device may be configured to adjust an amplitude of the second ECG signal in response to an enable signal, the enable signal being controlled based on the calculated first DC offset.
- the analog front end device is configured to adjust the amplitude of the second ECG signal such that a peak value is within a first reference range.
- the analog front end device is configured to calculate the first DC offset such that the first DC offset is within a second reference range.
- the analog front end device is configured to calculate the second DC offset based on a mean value of the second ECG signal.
- the analog front end device is configured to remove a third DC offset in a third ECG signal based on the calculated second DC offset, the third ECG signal being received subsequent to the second ECG signal.
- FIG. 1 is a schematic block diagram of an electrocardiogram (ECG) sensor according to at least one example embodiment of the inventive concepts
- FIG. 2 is a block diagram of an analog front end device (AFE) according to at least one example embodiment of the inventive concepts
- FIG. 3 is a diagram for explaining an operation of the AFE illustrated in FIG. 2 ;
- FIG. 4 is a flowchart of a method of processing a signal using a DC offset calculator illustrated in FIG. 2 according to at least example embodiment of the inventive concepts.
- FIG. 5 is a flowchart of a method of processing a signal using an automatic gain controller illustrated in FIG. 2 according to at least one example embodiment of the inventive concepts.
- terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical, electronic quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
- a process may be terminated when its operations are completed, but may also have additional steps not included in the figure.
- a process may correspond to a method, function, procedure, subroutine, subprogram, etc.
- a process corresponds to a function
- its termination may correspond to a return of the function to the calling function or the main function.
- the term “storage medium”, “computer readable storage medium” or “non-transitory computer readable storage medium” may represent one or more devices for storing data, including read only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other tangible or non-transitory machine readable mediums for storing information.
- ROM read only memory
- RAM random access memory
- magnetic RAM magnetic RAM
- core memory magnetic disk storage mediums
- optical storage mediums optical storage mediums
- flash memory devices and/or other tangible or non-transitory machine readable mediums for storing information.
- computer-readable medium may include, but is not limited to, portable or fixed storage devices, optical storage devices, and various other tangible or non-transitory mediums capable of storing, containing or carrying instruction(s) and/or data.
- example embodiments may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof.
- the program code or code segments to perform the necessary tasks may be stored in a machine or computer readable medium such as a computer readable storage medium.
- a processor or processors may be programmed to perform the necessary tasks, thereby being transformed into special purpose processor(s) or computer(s).
- the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.
- FIG. 1 is a schematic block diagram of an electrocardiogram (ECG) sensor 10 according to at least one example embodiment of the inventive concepts.
- the ECG sensor 10 may detect an ECG signal generated from parts (e.g., chest, arms, and legs) of a person's body by the person's heart and may transmit the ECG signal to a mobile device 20 .
- the ECG sensor 10 may include an analog front end device (AFE) 100 , a digital signal processor (DSP) 200 , and a radio frequency (RF) module 300 .
- AFE analog front end device
- DSP digital signal processor
- RF radio frequency
- the AFE 100 may remove a DC offset from an ECG signal ECG 1 received from a measuring electrode attached to a body, may adjust a gain amplification value of the signal ECG 1 , and may output a gain amplification value-adjusted ECG signal ECG 2 .
- the DSP 200 may analyze and process the ECG signal ECG 2 from the AFE 100 based on a desired (or alternatively, predetermined) algorithm and may detect and output information based on the analysis and processing.
- the RF module 300 may transmit the information output from the DSP 200 to the mobile device 20 via a wireless connection.
- the mobile device 20 may be a device, such as an ECG tester, a smart phone, a notebook computer, etc., that can communicate with the ECG sensor 10 in a wireless connection.
- the mobile device 20 may output the information received from the ECG sensor 10 in a form of image or voice that can be recognized by a user. In other words, the user is allowed to check the state of a patient's heart in real time based on the information output by the mobile device 20 .
- FIG. 2 is a block diagram of the AFE 100 according to at least one example embodiment of the inventive concepts.
- the AFE 100 may include an amplifier 110 , an analog-to-digital converter (ADC) 120 , an automatic gain controller 130 , a DC offset calculator 140 , and a digital-to-analog converter (DAC) 150 .
- ADC analog-to-digital converter
- DAC digital-to-analog converter
- the amplifier 110 may receive the ECG signal ECG 1 from a measuring electrode (e.g., on a patient's body) and may amplify the gain of the ECG signal ECG 1 based on a gain amplification value.
- the ADC 120 may perform analog-to-digital conversion on the gain-amplified ECG signal and may output a digital ECG signal.
- the automatic gain controller 130 may detect a peak value in the digital ECG signal output from the ADC 120 based on an enable signal EN and may output a gain amplification value that has been adjusted based on the peak value to the amplifier 110 .
- the amplifier 110 may adjust the gain of the ECG signal ECG 1 received from the measuring electrode based on the gain amplification value output from the automatic gain controller 130 .
- the automatic gain controller 130 may include a timer (not shown) to count a desired (or alternatively, predetermined) time so that the adjusted gain amplification value is applied when the gain of the ECG signal ECG 1 received from the measuring electrode is desired to be adjusted. While the timer is performing a counting operation, the automatic gain controller 130 may not perform an operation of adjusting the gain amplification value with respect to ECG signals output from the ADC 120 but may instead continuously output the same gain amplification value that has been adjusted.
- the DC offset calculator 140 may calculate a DC offset in the digital ECG signal output from the ADC 120 and may output the DC offset.
- the DC offset calculator 140 may output the enable signal EN for adjusting the gain amplification value of an ECG signal to the automatic gain controller 130 after calculating and outputting the DC offset in the ECG signal during the initial operation of the ECG sensor 10 .
- the DAC 150 may perform digital-to-analog conversion on the DC offset output from the DC offset calculator 140 and may output an analog DC offset to the amplifier 110 .
- the amplifier 110 may remove the DC offset from the ECG signal ECG 1 received from the measuring electrode based on the analog DC offset to send an ECG signal ECG 2 to ADC 120 .
- the ADC 120 may output the ECG signal ECG 2 , which corresponds to a result of removing the DC offset from the ECG signal ECG 1 and adjusting the gain of the ECG signal ECG 1 , to the DSP 200 .
- FIG. 3 is a diagram for explaining an operation of the AFE 100 illustrated in FIG. 2 .
- the AFE 100 may remove a DC offset from an ECG signal E 1 received from a measuring electrode during a first period T coarse, and then may remove a DC offset from ECG signals E 2 , E 3 , and E 4 received during a second period T fine and simultaneously adjust a gain amplification value of ECG signals E 2 , E 3 , and E 4 .
- the first period T coarse and the second period T fine may be the same duration. However, while the first period T coarse is for removing a DC offset from an ECG signal received from a measuring electrode, the second period T fine is for removing a DC offset from a subsequent ECG signal received after DC offset removing is once performed in T coarse and for simultaneously adjusting the gain amplification value of the subsequent ECG signal.
- the DC offset calculator 140 may calculate a DC offset in the ECG signal E 1 received during the first period T coarse and may output a bit value corresponding to the DC offset to the DAC 150 . Thereafter, the DC offset calculator 140 may calculate a mean value of the ECG signal E 2 received during the second period T fine , may calculate a DC offset for the mean value, and may determine whether the DC offset is in a first reference range between offset_L and offset_H.
- the DC offset calculator 140 may output a bit value corresponding to the DC offset that has been decreased or increased with respect to the ECG signal E 2 to the DAC 150 .
- a DC offset is calculated with respect to the mean value of an ECG signal received during the second period T fine .
- the DC offset calculated during the second period T fine may be less than the DC offset calculated with respect to an ECG signal received during the first period T coarse .
- the DC offset calculator 140 may calculate and output a DC offset with respect to a mean value of an ECG signal E 2 _ 1 and the automatic gain controller 130 may output an adjusted gain amplification value with respect to the ECG signal E 2 _ 1 .
- the automatic gain controller 130 may determine whether a peak value of the ECG signal E 2 _ 1 is in a second reference range IR and may output a bit value, which corresponds to a gain amplification value that has been decreased or increased with respect to the ECG signal E 2 _ 1 based on the determination result, to the amplifier 110 .
- the automatic gain controller 130 may output a bit value for increasing the gain amplification value to the amplifier 110 and may output an ECG signal E 2 _ 2 obtained after a gain has been increased to the DSP 200 .
- the automatic gain controller 130 may output a bit value for decreasing the gain amplification value to the amplifier 110 and may output an ECG signal E 3 _ 2 obtained after a gain has been decreased to the DSP 200 .
- the DC offset may be in the first reference range between offset_L and offset_H and the peak value of an ECG signal E 4 may be in the second reference range IR, as shown in the ECG signal E 4 .
- the magnitude of an ECG signal that has been measured may be maintained in a desired (or alternatively, predetermined) range, so that a user is allowed to get more accurate information.
- FIG. 4 is a flowchart of a method of processing a signal using the DC offset calculator 140 illustrated in FIG. 2 according to at least one example embodiment of the inventive concepts.
- the DC offset calculator 140 may perform the method illustrated in FIG. 4 .
- the DC offset calculator 140 calculates a DC offset in an ECG signal received during the first period T coarse in operation S 401 and outputs the DC offset to the DAC 150 in operation S 402 .
- the DC offset calculator 140 calculates a DC offset with respect to a mean value of an ECG signal received during the second period T fine in operation S 403 and determines whether the DC offset is greater than a first reference value offset L in operation S 404 .
- the DC offset calculator 140 In operation S 405 , when the DC offset is less than the first reference value offset_L, the DC offset calculator 140 outputs a bit value corresponding to a DC offset that has been increased with respect to the mean value of the ECG signal to the DAC 150 . When the DC offset is determined as greater than the first reference value offset_L in operation S 405 , the DC offset calculator 140 determines whether the DC offset is less than a second reference value offset_H in operation S 406 .
- the DC offset calculator 140 In operation S 407 , when the DC offset is greater than the second reference value offset_H, the DC offset calculator 140 outputs a bit value corresponding to a DC offset that has been decreased with respect to the mean value of the ECG signal to the DAC 150 . In operation S 408 , when the DC offset is determined as less than the second reference value offset_H in operation S 406 , the DC offset calculator 140 outputs the enable signal EN to the automatic gain controller 130 in order to adjust the gain of the ECG signal.
- the DC offset calculator 140 calculates a DC offset with respect to the mean value of an ECG signal received during another second period T fine .
- the DC offset calculator 140 determines whether the DC offset is higher than the first reference value offset_L.
- the DC offset calculator 140 In operation S 411 , when the DC offset is less than the first reference value offset_L, the DC offset calculator 140 outputs a bit value corresponding to a DC offset that has been increased with respect to the mean value of the ECG signal to the DAC 150 .
- the DC offset calculator 140 determines whether the DC offset is less than a second reference value offset_H in operation S 412 .
- the DC offset calculator 140 when the DC offset is greater than the second reference value offset_H, the DC offset calculator 140 outputs a bit value corresponding to a DC offset that has been decreased with respect to the mean value of the ECG signal to the DAC 150 .
- the DC offset calculator 140 may perform operations S 409 through S 412 on a subsequent ECG signal.
- Operations S 401 through S 407 illustrated in FIG. 4 are performed in the initial operation of the ECG sensor 10 (e.g., on the signal E 1 in FIG. 3 ) and operations S 409 through S 413 may be repeated after the initial operation of the ECG sensor 10 (e.g., on signals E 2 , E 3 , and E 4 in FIG. 3 ).
- Operations S 401 through S 407 may be performed based on a gain amplification value (or a reference gain amplification value) initially set by the automatic gain controller 130 and operations S 409 through S 413 may be performed while the gain amplification value is being adjusted by the automatic gain controller 130 .
- the reference gain amplification value may be user defined and/or based on empirical evidence.
- a gain amplification value applied to the amplifier 110 in operations S 403 through S 407 may be less than a gain amplification value applied to the amplifier 110 in operations S 409 through S 413 .
- FIG. 5 is a flowchart of a method of processing a signal using the automatic gain controller 130 illustrated in FIG. 2 according to at least one example embodiment of the inventive concepts.
- the automatic gain controller 130 may perform the method illustrated in FIG. 5 .
- the automatic gain controller 130 outputs an initially set reference gain amplification value to the amplifier 110 in operation S 501 .
- the automatic gain controller 130 detects a peak value of an ECG signal received from the ADC 120 in operation S 502 and determines whether the peak value is lower than the first reference value min_level in operation S 503 .
- the automatic gain controller 130 when the peak value is lower than the first reference value min_level, the automatic gain controller 130 outputs a bit value corresponding to a gain amplification value that has been increased with respect to the ECG signal to the amplifier 110 .
- the automatic gain controller 130 determines whether the peak value is higher than the second reference value max_level.
- the automatic gain controller 130 when the peak value is higher than the second reference value max_level, the automatic gain controller 130 outputs a bit value corresponding to a gain amplification value that has been decreased with respect to the ECG signal to the amplifier 110 .
- the automatic gain controller 130 In order to apply the gain amplification value that has been adjusted to the AFE 100 in operations S 504 and S 506 , the automatic gain controller 130 outputs a control signal to a timer (not shown) in operation S 507 so that a counting operation is performed based on desired (or alternatively, predetermined) time information. After the desired (or alternatively, predetermined) period of time, the automatic gain controller 130 resets the timer in operation S 508 .
- the automatic gain controller 130 may continuously output the adjusted gain amplification value to the amplifier 110 in operation S 504 or S 506 .
- the inventive concepts may also be embodied as computer readable codes on a computer readable recording medium.
- the computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, and optical data storage devices.
- the computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. Also, functional programs, codes, and code segments for accomplishing the inventive concepts can be easily construed by programmers skilled in the art to which the inventive concepts pertain.
- an ECG sensor minimizes a DC offset and also automatically adjusts the gain of an amplifier, so that the magnitude of a measured ECG signal is maintained in a desired (or alternatively, predetermined) range. As a result, the ECG signal is detected more accurately.
Abstract
Description
- This application claims priority under 35 U.S.C.§119(a) from Korean Patent Application No. 10-2014-0016898 filed on Feb. 13, 2014, the disclosure of which is hereby incorporated by reference in its entirety.
- At least one example embodiment of the inventive concepts relates to an electrocardiogram (ECG) sensor, and more particularly, to an ECG sensor capable of performing DC offset and gain adjustment at one time and/or a method of processing a signal using the same.
- An ECG sensor is usually used to measure an ECG of a patient's heart. The ECG sensor processes and analyzes a signal measured from an electrode directly contacting a patient's body and the patient's physical condition can be evaluated using ECG signals output from the ECG sensor.
- Recently, as people's interest in health increases, it is desired to display or transmit a patient's physical condition based on an ECG signal measured by an ECG sensor to an external device through a connection to a communication system. This enables fast treatment, early diagnosis, and prevention. However, when motion artifacts or DC offsets are introduced to the ECG signal measured by the ECG sensor, it is difficult to correctly analyze an original signal.
- According to at least one example embodiment of the inventive concepts, an electrocardiogram (ECG) sensor includes an analog front end device configured to remove a DC offset in a first ECG signal received from a measuring electrode, and adjust a gain amplification value based on the first ECG signal. The analog front end device is configured to output an adjusted first ECG signal, the adjusted first ECG signal being based on the adjusted gain amplification value and the removed DC offset in the first ECG signal. The ECG sensor includes a digital signal processor configured to analyze and process the adjusted first ECG signal based on an algorithm and to output information. The analog front end device is configured to remove the DC offset in the first ECG signal during a first period, and remove a DC offset in a second ECG signal and simultaneously adjust a gain amplification value for the second ECG signal during a second period.
- According to at least one example embodiment the analog front end device (AFE) comprises an amplifier configured to receive the first ECG signal from the measuring electrode and amplify the first ECG signal based on the gain amplification value for the first ECG signal. The AFE includes an analog-to-digital converter configured to perform analog-to-digital conversion on the amplified first ECG signal and output a digital ECG signal. The AFE includes an automatic gain controller configured to detect a peak value of the digital ECG signal and to adjust the gain amplification value for the adjusted first ECG signal based on the peak value.
- According to at least one example embodiment, the AFE further comprises a DC offset calculator configured to calculate a mean value of the digital ECG signal, calculate a DC offset with respect to the mean value, and output the DC offset calculated with respect to the mean value. The AFE includes a digital-to-analog converter configured to perform digital-to-analog conversion on the DC offset output from the DC offset calculator to output an analog DC offset. The amplifier is configured to remove the DC offset from the first ECG signal based on the analog DC offset.
- According to at least one example embodiment, the DC offset calculator is configured to determine whether the DC offset calculated with respect to the mean value is in a first reference range.
- According to at least one example embodiment, the DC offset calculator is configured to output a bit value corresponding to a changed DC offset with respect to the digital ECG signal if the DC offset calculated with respect to the mean value is not in the first reference range, the bit value being output to the digital-to-analog converter.
- According to at least one example embodiment, the automatic gain controller is configured to detect the peak value of the digital ECG signal and to determine whether the detected peak value is in a second reference range.
- According to at least one example embodiment, the automatic gain controller is configured to output a bit value corresponding to a changed gain amplification value with respect to the digital ECG signal if the detected peak value is not in the second reference range, the bit value being output to the amplifier.
- According to at least one example embodiment the automatic gain controller comprises a timer configured to count a time during which the adjusted gain amplification value is applied to one of the first and second ECG signals.
- According to at least one example embodiment the ECG sensor includes a radio frequency (RF) module configured to transmit the information detected by the digital signal processor via a wireless connection.
- According to at least one example embodiment a method of processing a signal using an electrocardiogram (ECG) sensor includes calculating, by the ECG sensor, a DC offset in an initial ECG signal received from a measuring electrode during a first period. The method includes removing, by the ECG sensor, a DC offset from a first ECG signal received during a second period, the removing being based on the calculated DC offset in the initial ECG signal. The method includes calculating, by the ECG sensor, a DC offset in a second ECG signal received during the second period and adjusting a gain amplification value for the second ECG signal.
- According to at least one example embodiment, the calculating the DC offset in the second ECG signal comprises calculating a DC offset with respect to a mean value of the second ECG signal, determining whether the DC offset is in a first reference range, and outputting a bit value corresponding to a decreased or increased DC offset with respect to the second ECG signal if the DC offset is not in the first reference range.
- According to at least one example embodiment, the adjusting the gain amplification value for the second ECG signal comprises detecting a peak value of the second ECG signal, determining whether the peak value is in a second reference range, and outputting a bit value corresponding to a decreased or increased gain amplification value with respect to the second ECG signal if the peak value is not in the second reference range.
- According to at least one example embodiment, the calculating the DC offset in the second ECG signal and the adjusting the gain amplification value for the second ECG signal are performed simultaneously and repeatedly while the ECG sensor is operating.
- According to at least one example embodiment, a device, comprises an analog front end device configured to calculate a first DC offset in a first ECG signal received from a measuring electrode, and remove a second DC offset in a second ECG signal based on the calculated first DC offset. The second ECG signal may be received subsequent to the first ECG signal. The analog front end device may be configured to adjust an amplitude of the second ECG signal in response to an enable signal, the enable signal being controlled based on the calculated first DC offset.
- According to at least one example embodiment, the analog front end device is configured to adjust the amplitude of the second ECG signal such that a peak value is within a first reference range.
- According to at least one example embodiment, the analog front end device is configured to calculate the first DC offset such that the first DC offset is within a second reference range.
- According to at least one example embodiment, wherein the analog front end device is configured to calculate the second DC offset based on a mean value of the second ECG signal.
- According to at least one example embodiment, wherein the analog front end device is configured to remove a third DC offset in a third ECG signal based on the calculated second DC offset, the third ECG signal being received subsequent to the second ECG signal.
- The above and other features and advantages of the inventive concepts will become more apparent by describing in detail example embodiments thereof with reference to the attached drawings in which:
-
FIG. 1 is a schematic block diagram of an electrocardiogram (ECG) sensor according to at least one example embodiment of the inventive concepts; -
FIG. 2 is a block diagram of an analog front end device (AFE) according to at least one example embodiment of the inventive concepts; -
FIG. 3 is a diagram for explaining an operation of the AFE illustrated inFIG. 2 ; -
FIG. 4 is a flowchart of a method of processing a signal using a DC offset calculator illustrated inFIG. 2 according to at least example embodiment of the inventive concepts; and -
FIG. 5 is a flowchart of a method of processing a signal using an automatic gain controller illustrated inFIG. 2 according to at least one example embodiment of the inventive concepts. - Inventive concepts will now be described more fully with reference to the accompanying drawings, in which example embodiments of are shown. These example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey inventive concepts of to those skilled in the art. Inventive concepts may be embodied in many different forms with a variety of modifications, and a few embodiments will be illustrated in drawings and explained in detail. However, this should not be construed as being limited to example embodiments set forth herein, and rather, it should be understood that changes may be made in these example embodiments without departing from the principles and spirit of inventive concepts, the scope of which are defined in the claims and their equivalents. Like numbers refer to like elements throughout. In the drawings, the thicknesses of layers and regions are exaggerated for clarity.
- It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
- It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.).
- Unless specifically stated otherwise, or as is apparent from the discussion, terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical, electronic quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
- Specific details are provided in the following description to provide a thorough understanding of example embodiments. However, it will be understood by one of ordinary skill in the art that example embodiments may be practiced without these specific details. For example, systems may be shown in block diagrams so as not to obscure example embodiments in unnecessary detail. In other instances, well-known processes, structures and techniques may be shown without unnecessary detail in order to avoid obscuring example embodiments.
- In the following description, illustrative embodiments will be described with reference to acts and symbolic representations of operations (e.g., in the form of flow charts, flow diagrams, data flow diagrams, structure diagrams, block diagrams, etc.) that may be implemented as program modules or functional processes include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types and may be implemented using existing hardware in existing electronic systems (e.g., electronic imaging systems, image processing systems, digital point-and-shoot cameras, personal digital assistants (PDAs), smartphones, tablet personal computers (PCs), laptop computers, etc.). Such existing hardware may include one or more Central Processing Units (CPUs), digital signal processors (DSPs), application-specific-integrated-circuits (ASICs), field programmable gate arrays (FPGAs) computers or the like.
- Although a flow chart may describe the operations as a sequential process, many of the operations may be performed in parallel, concurrently or simultaneously. In addition, the order of the operations may be re-arranged. A process may be terminated when its operations are completed, but may also have additional steps not included in the figure. A process may correspond to a method, function, procedure, subroutine, subprogram, etc. When a process corresponds to a function, its termination may correspond to a return of the function to the calling function or the main function.
- As disclosed herein, the term “storage medium”, “computer readable storage medium” or “non-transitory computer readable storage medium” may represent one or more devices for storing data, including read only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other tangible or non-transitory machine readable mediums for storing information. The term “computer-readable medium” may include, but is not limited to, portable or fixed storage devices, optical storage devices, and various other tangible or non-transitory mediums capable of storing, containing or carrying instruction(s) and/or data.
- Furthermore, example embodiments may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine or computer readable medium such as a computer readable storage medium. When implemented in software, a processor or processors may be programmed to perform the necessary tasks, thereby being transformed into special purpose processor(s) or computer(s).
- The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes”, “including”, “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
- Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which inventive concepts belong. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
- As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.
-
FIG. 1 is a schematic block diagram of an electrocardiogram (ECG)sensor 10 according to at least one example embodiment of the inventive concepts. Referring toFIG. 1 , theECG sensor 10 may detect an ECG signal generated from parts (e.g., chest, arms, and legs) of a person's body by the person's heart and may transmit the ECG signal to amobile device 20. TheECG sensor 10 may include an analog front end device (AFE) 100, a digital signal processor (DSP) 200, and a radio frequency (RF)module 300. - The
AFE 100 may remove a DC offset from an ECG signal ECG1 received from a measuring electrode attached to a body, may adjust a gain amplification value of the signal ECG1, and may output a gain amplification value-adjusted ECG signal ECG2. TheDSP 200 may analyze and process the ECG signal ECG2 from theAFE 100 based on a desired (or alternatively, predetermined) algorithm and may detect and output information based on the analysis and processing. TheRF module 300 may transmit the information output from theDSP 200 to themobile device 20 via a wireless connection. - The
mobile device 20 may be a device, such as an ECG tester, a smart phone, a notebook computer, etc., that can communicate with theECG sensor 10 in a wireless connection. Themobile device 20 may output the information received from theECG sensor 10 in a form of image or voice that can be recognized by a user. In other words, the user is allowed to check the state of a patient's heart in real time based on the information output by themobile device 20. -
FIG. 2 is a block diagram of theAFE 100 according to at least one example embodiment of the inventive concepts. Referring toFIG. 2 , theAFE 100 may include anamplifier 110, an analog-to-digital converter (ADC) 120, anautomatic gain controller 130, a DC offsetcalculator 140, and a digital-to-analog converter (DAC) 150. - The
amplifier 110 may receive the ECG signal ECG1 from a measuring electrode (e.g., on a patient's body) and may amplify the gain of the ECG signal ECG1 based on a gain amplification value. TheADC 120 may perform analog-to-digital conversion on the gain-amplified ECG signal and may output a digital ECG signal. - The
automatic gain controller 130 may detect a peak value in the digital ECG signal output from theADC 120 based on an enable signal EN and may output a gain amplification value that has been adjusted based on the peak value to theamplifier 110. Theamplifier 110 may adjust the gain of the ECG signal ECG1 received from the measuring electrode based on the gain amplification value output from theautomatic gain controller 130. - The
automatic gain controller 130 may include a timer (not shown) to count a desired (or alternatively, predetermined) time so that the adjusted gain amplification value is applied when the gain of the ECG signal ECG1 received from the measuring electrode is desired to be adjusted. While the timer is performing a counting operation, theautomatic gain controller 130 may not perform an operation of adjusting the gain amplification value with respect to ECG signals output from theADC 120 but may instead continuously output the same gain amplification value that has been adjusted. - The DC offset
calculator 140 may calculate a DC offset in the digital ECG signal output from theADC 120 and may output the DC offset. The DC offsetcalculator 140 may output the enable signal EN for adjusting the gain amplification value of an ECG signal to theautomatic gain controller 130 after calculating and outputting the DC offset in the ECG signal during the initial operation of theECG sensor 10. - The
DAC 150 may perform digital-to-analog conversion on the DC offset output from the DC offsetcalculator 140 and may output an analog DC offset to theamplifier 110. Theamplifier 110 may remove the DC offset from the ECG signal ECG1 received from the measuring electrode based on the analog DC offset to send an ECG signal ECG2 toADC 120. TheADC 120 may output the ECG signal ECG2, which corresponds to a result of removing the DC offset from the ECG signal ECG1 and adjusting the gain of the ECG signal ECG1, to theDSP 200. -
FIG. 3 is a diagram for explaining an operation of theAFE 100 illustrated inFIG. 2 . Referring toFIGS. 2 and 3 , theAFE 100 may remove a DC offset from an ECG signal E1 received from a measuring electrode during a first period Tcoarse, and then may remove a DC offset from ECG signals E2, E3, and E4 received during a second period Tfine and simultaneously adjust a gain amplification value of ECG signals E2, E3, and E4. - The first period Tcoarse and the second period Tfine may be the same duration. However, while the first period Tcoarse is for removing a DC offset from an ECG signal received from a measuring electrode, the second period Tfine is for removing a DC offset from a subsequent ECG signal received after DC offset removing is once performed in Tcoarse and for simultaneously adjusting the gain amplification value of the subsequent ECG signal.
- The DC offset
calculator 140 may calculate a DC offset in the ECG signal E1 received during the first period Tcoarse and may output a bit value corresponding to the DC offset to theDAC 150. Thereafter, the DC offsetcalculator 140 may calculate a mean value of the ECG signal E2 received during the second period Tfine, may calculate a DC offset for the mean value, and may determine whether the DC offset is in a first reference range between offset_L and offset_H. - When the DC offset is not in the first reference range between offset_L and offset_H, the DC offset
calculator 140 may output a bit value corresponding to the DC offset that has been decreased or increased with respect to the ECG signal E2 to theDAC 150. At this time, a DC offset is calculated with respect to the mean value of an ECG signal received during the second period Tfine. The DC offset calculated during the second period Tfine may be less than the DC offset calculated with respect to an ECG signal received during the first period Tcoarse. - In other words, after a DC offset is removed from an ECG signal received during the second period Tfine based on a DC offset calculated during the first period Tcoarse, the DC offset
calculator 140 may calculate and output a DC offset with respect to a mean value of an ECG signal E2_1 and theautomatic gain controller 130 may output an adjusted gain amplification value with respect to the ECG signal E2_1. At this time, theautomatic gain controller 130 may determine whether a peak value of the ECG signal E2_1 is in a second reference range IR and may output a bit value, which corresponds to a gain amplification value that has been decreased or increased with respect to the ECG signal E2_1 based on the determination result, to theamplifier 110. - When the peak value is lower than a first reference value min_level, the
automatic gain controller 130 may output a bit value for increasing the gain amplification value to theamplifier 110 and may output an ECG signal E2_2 obtained after a gain has been increased to theDSP 200. In addition, when a peak value of an ECG signal E3_1 is higher than a second reference value max level, theautomatic gain controller 130 may output a bit value for decreasing the gain amplification value to theamplifier 110 and may output an ECG signal E3_2 obtained after a gain has been decreased to theDSP 200. - Consequently, when the above-described procedure is repeated during the second period Tfine, the DC offset may be in the first reference range between offset_L and offset_H and the peak value of an ECG signal E4 may be in the second reference range IR, as shown in the ECG signal E4. As a result, the magnitude of an ECG signal that has been measured may be maintained in a desired (or alternatively, predetermined) range, so that a user is allowed to get more accurate information.
-
FIG. 4 is a flowchart of a method of processing a signal using the DC offsetcalculator 140 illustrated inFIG. 2 according to at least one example embodiment of the inventive concepts. When an ECG signal is received from theADC 120 after theECG sensor 10 starts, the DC offsetcalculator 140 may perform the method illustrated inFIG. 4 . - Referring to
FIGS. 2 through 4 , the DC offsetcalculator 140 calculates a DC offset in an ECG signal received during the first period Tcoarse in operation S401 and outputs the DC offset to theDAC 150 in operation S402. The DC offsetcalculator 140 calculates a DC offset with respect to a mean value of an ECG signal received during the second period Tfine in operation S403 and determines whether the DC offset is greater than a first reference value offset L in operation S404. - In operation S405, when the DC offset is less than the first reference value offset_L, the DC offset
calculator 140 outputs a bit value corresponding to a DC offset that has been increased with respect to the mean value of the ECG signal to theDAC 150. When the DC offset is determined as greater than the first reference value offset_L in operation S405, the DC offsetcalculator 140 determines whether the DC offset is less than a second reference value offset_H in operation S406. - In operation S407, when the DC offset is greater than the second reference value offset_H, the DC offset
calculator 140 outputs a bit value corresponding to a DC offset that has been decreased with respect to the mean value of the ECG signal to theDAC 150. In operation S408, when the DC offset is determined as less than the second reference value offset_H in operation S406, the DC offsetcalculator 140 outputs the enable signal EN to theautomatic gain controller 130 in order to adjust the gain of the ECG signal. - Thereafter, in operation S409, the DC offset
calculator 140 calculates a DC offset with respect to the mean value of an ECG signal received during another second period Tfine. In operation S410, the DC offsetcalculator 140 determines whether the DC offset is higher than the first reference value offset_L. - In operation S411, when the DC offset is less than the first reference value offset_L, the DC offset
calculator 140 outputs a bit value corresponding to a DC offset that has been increased with respect to the mean value of the ECG signal to theDAC 150. When the DC offset is determined as greater than the first reference value offset_L in operation S410, the DC offsetcalculator 140 determines whether the DC offset is less than a second reference value offset_H in operation S412. - In operation S413, when the DC offset is greater than the second reference value offset_H, the DC offset
calculator 140 outputs a bit value corresponding to a DC offset that has been decreased with respect to the mean value of the ECG signal to theDAC 150. When the DC offset is determined as less than the second reference value offset_H in operation S412, the DC offsetcalculator 140 may perform operations S409 through S412 on a subsequent ECG signal. - Operations S401 through S407 illustrated in
FIG. 4 are performed in the initial operation of the ECG sensor 10 (e.g., on the signal E1 inFIG. 3 ) and operations S409 through S413 may be repeated after the initial operation of the ECG sensor 10 (e.g., on signals E2, E3, and E4 inFIG. 3 ). Operations S401 through S407 may be performed based on a gain amplification value (or a reference gain amplification value) initially set by theautomatic gain controller 130 and operations S409 through S413 may be performed while the gain amplification value is being adjusted by theautomatic gain controller 130. The reference gain amplification value may be user defined and/or based on empirical evidence. At this time, a gain amplification value applied to theamplifier 110 in operations S403 through S407 may be less than a gain amplification value applied to theamplifier 110 in operations S409 through S413. -
FIG. 5 is a flowchart of a method of processing a signal using theautomatic gain controller 130 illustrated inFIG. 2 according to at least one example embodiment of the inventive concepts. When receiving an ECG signal from theADC 120 after theECG sensor 10 starts and receiving the enable signal EN from the DC offsetcalculator 140, theautomatic gain controller 130 may perform the method illustrated inFIG. 5 . - Referring to
FIGS. 2 through 5 , theautomatic gain controller 130 outputs an initially set reference gain amplification value to theamplifier 110 in operation S501. Theautomatic gain controller 130 detects a peak value of an ECG signal received from theADC 120 in operation S502 and determines whether the peak value is lower than the first reference value min_level in operation S503. - In operation S504, when the peak value is lower than the first reference value min_level, the
automatic gain controller 130 outputs a bit value corresponding to a gain amplification value that has been increased with respect to the ECG signal to theamplifier 110. In operation S505, when the peak value is determined as higher than the first reference value min_level, theautomatic gain controller 130 determines whether the peak value is higher than the second reference value max_level. - In operation S506, when the peak value is higher than the second reference value max_level, the
automatic gain controller 130 outputs a bit value corresponding to a gain amplification value that has been decreased with respect to the ECG signal to theamplifier 110. - In order to apply the gain amplification value that has been adjusted to the
AFE 100 in operations S504 and S506, theautomatic gain controller 130 outputs a control signal to a timer (not shown) in operation S507 so that a counting operation is performed based on desired (or alternatively, predetermined) time information. After the desired (or alternatively, predetermined) period of time, theautomatic gain controller 130 resets the timer in operation S508. - Instead of performing operations S502 through S506, the
automatic gain controller 130 may continuously output the adjusted gain amplification value to theamplifier 110 in operation S504 or S506. - The inventive concepts may also be embodied as computer readable codes on a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, and optical data storage devices. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. Also, functional programs, codes, and code segments for accomplishing the inventive concepts can be easily construed by programmers skilled in the art to which the inventive concepts pertain.
- As described above, according to at least one example embodiment of the inventive concepts, an ECG sensor minimizes a DC offset and also automatically adjusts the gain of an amplifier, so that the magnitude of a measured ECG signal is maintained in a desired (or alternatively, predetermined) range. As a result, the ECG signal is detected more accurately.
- While the inventive concepts have been particularly shown and described with reference to example embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in forms and details may be made therein without departing from the spirit and scope of the inventive concepts as defined by the following claims.
Claims (20)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020140016898A KR102151697B1 (en) | 2014-02-13 | 2014-02-13 | Electrocardiogram sensor and signal processing method thereof |
KR10-2014-0016898 | 2014-02-13 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20150223758A1 true US20150223758A1 (en) | 2015-08-13 |
US9326732B2 US9326732B2 (en) | 2016-05-03 |
Family
ID=53773894
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/598,918 Active US9326732B2 (en) | 2014-02-13 | 2015-01-16 | Electrocardiogram sensor and method of processing signals using the same |
Country Status (2)
Country | Link |
---|---|
US (1) | US9326732B2 (en) |
KR (1) | KR102151697B1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170344505A1 (en) * | 2016-05-25 | 2017-11-30 | Realtek Semiconductor Corporation | Data Processing Circuit and Data Processing Method |
CN107452417A (en) * | 2016-06-01 | 2017-12-08 | 瑞昱半导体股份有限公司 | Data processing circuit and data processing method |
JP2018030276A (en) * | 2016-08-23 | 2018-03-01 | コニカミノルタ株式会社 | Image processing apparatus, and stress measuring method and program therefor |
CN109589109A (en) * | 2017-10-03 | 2019-04-09 | 韦伯斯特生物官能(以色列)有限公司 | Midpoint zero refers to |
WO2019175156A1 (en) * | 2018-03-13 | 2019-09-19 | Cathvision Aps | System and method for processing electrophysiological signals |
EP4021293A4 (en) * | 2019-08-28 | 2023-08-09 | Rds | Vital signs or health monitoring systems and methods |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20170061243A (en) * | 2015-11-25 | 2017-06-05 | 티엠에스비엠이 주식회사 | An ECG sensor system with electrode pattern for improving signal-to-noise ratio |
KR101934487B1 (en) | 2016-11-28 | 2019-01-03 | 티엠에스비엠이 주식회사 | An ECG sensor system with trisection electrode pattern |
KR102126002B1 (en) * | 2019-12-13 | 2020-06-24 | 주식회사 파낙토스 | Brain Wave Measuring Device |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080119716A1 (en) * | 2006-05-17 | 2008-05-22 | Olga Boric-Lubecke | Determining presence and/or physiological motion of one or more subjects with quadrature doppler radar receiver systems |
US20100237851A1 (en) * | 2006-06-16 | 2010-09-23 | Hans Gerard Leonard Coster | system for complex impedance measurement |
US20100246643A1 (en) * | 2006-11-16 | 2010-09-30 | In-Gi Lim | System and method for human body communication using limited passband |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ZA95605B (en) | 1994-04-28 | 1995-12-20 | Qualcomm Inc | Method and apparatus for automatic gain control and dc offset cancellation in quadrature receiver |
EP1201029B1 (en) | 1999-05-24 | 2003-04-02 | Level One Communications, Inc | Automatic gain control and offset correction |
US6697611B1 (en) | 2000-11-14 | 2004-02-24 | Intel Corporation | Method and apparatus for performing DC offset cancellation in a receiver |
US6510339B2 (en) | 2000-12-06 | 2003-01-21 | Cardiac Pacemakers, Inc. | ECG auto-gain control |
US7110734B2 (en) | 2002-09-05 | 2006-09-19 | Maxim Integrated Products Inc. | DC offset cancellation in a zero if receiver |
KR100527000B1 (en) | 2003-04-10 | 2005-11-08 | 한국전자통신연구원 | Automatic gain control apparatus capable of compensating dc offset in orthogonal frequency division multipexing and method thereof |
US7372925B2 (en) | 2004-06-09 | 2008-05-13 | Theta Microelectronics, Inc. | Wireless LAN receiver with I and Q RF and baseband AGC loops and DC offset cancellation |
TWI261964B (en) | 2005-06-22 | 2006-09-11 | Ind Tech Res Inst | DC offset removing circuit of trans-impedance amplifier and automatic gain control trans-impedance amplifier |
KR100868073B1 (en) * | 2006-09-18 | 2008-11-10 | 연세대학교 산학협력단 | Armband type measurment unit of bio-signal |
US7695085B2 (en) | 2007-09-17 | 2010-04-13 | Finisar Corporation | Variable gain amplifier having variable gain DC offset loop |
GB0816571D0 (en) | 2008-09-10 | 2008-10-15 | Cambridge Silicon Radio Ltd | Automatic gain control & DC offset compensation |
US8666343B2 (en) | 2008-09-15 | 2014-03-04 | Analog Devices, Inc. | DC-offset-correction system and method for communication receivers |
US8212942B2 (en) | 2010-04-14 | 2012-07-03 | Newport Media, Inc. | All digital front-end architecture for television with sigma-delta ADC input |
-
2014
- 2014-02-13 KR KR1020140016898A patent/KR102151697B1/en active IP Right Grant
-
2015
- 2015-01-16 US US14/598,918 patent/US9326732B2/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080119716A1 (en) * | 2006-05-17 | 2008-05-22 | Olga Boric-Lubecke | Determining presence and/or physiological motion of one or more subjects with quadrature doppler radar receiver systems |
US20100237851A1 (en) * | 2006-06-16 | 2010-09-23 | Hans Gerard Leonard Coster | system for complex impedance measurement |
US20100246643A1 (en) * | 2006-11-16 | 2010-09-30 | In-Gi Lim | System and method for human body communication using limited passband |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170344505A1 (en) * | 2016-05-25 | 2017-11-30 | Realtek Semiconductor Corporation | Data Processing Circuit and Data Processing Method |
US10102167B2 (en) * | 2016-05-25 | 2018-10-16 | Realtek Semiconductor Corporation | Data processing circuit and data processing method |
CN107452417A (en) * | 2016-06-01 | 2017-12-08 | 瑞昱半导体股份有限公司 | Data processing circuit and data processing method |
JP2018030276A (en) * | 2016-08-23 | 2018-03-01 | コニカミノルタ株式会社 | Image processing apparatus, and stress measuring method and program therefor |
CN109589109A (en) * | 2017-10-03 | 2019-04-09 | 韦伯斯特生物官能(以色列)有限公司 | Midpoint zero refers to |
WO2019175156A1 (en) * | 2018-03-13 | 2019-09-19 | Cathvision Aps | System and method for processing electrophysiological signals |
US11737698B2 (en) | 2018-03-13 | 2023-08-29 | Cathvision Aps | System and method for processing electrophysiological signals |
EP4021293A4 (en) * | 2019-08-28 | 2023-08-09 | Rds | Vital signs or health monitoring systems and methods |
Also Published As
Publication number | Publication date |
---|---|
US9326732B2 (en) | 2016-05-03 |
KR20150095496A (en) | 2015-08-21 |
KR102151697B1 (en) | 2020-09-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9326732B2 (en) | Electrocardiogram sensor and method of processing signals using the same | |
US11770619B2 (en) | Generating static images with an event camera | |
KR102503684B1 (en) | Electronic apparatus and operating method thereof | |
CN108431764B (en) | Electronic device and method for controlling operation of electronic device | |
EP2896359A1 (en) | Method and system for measuring heart rate in electronic device using photoplethysmography | |
US20170086779A1 (en) | Eating and drinking action detection apparatus and eating and drinking action detection method | |
US20150190077A1 (en) | Electronic device and photoplethysmography method | |
KR102339798B1 (en) | Method for processing sound of electronic device and electronic device thereof | |
KR20180090695A (en) | Electronic device for capturing image based on difference between a plurality of images and method thereof | |
EP3915469A1 (en) | Apparatus and method for estimating cardiovascular information | |
CN111200304B (en) | Temperature detection circuit, method and device of wireless charging coil and storage medium | |
KR20150103586A (en) | Method for processing voice input and electronic device using the same | |
US20190167200A1 (en) | Bio-signal quality assessment apparatus and bio-signal quality assessment method | |
KR102362121B1 (en) | Electronic device and input and output method thereof | |
US11284805B2 (en) | Blood pressure estimating apparatus, method for estimating blood pressure, and non-transitory computer-readable recording medium having stored therein program for estimating blood pressure | |
CN107466240A (en) | Apparatus and method for producing flow distribution | |
KR20180036464A (en) | Method for Processing Image and the Electronic Device supporting the same | |
EP4184907A1 (en) | Zooming method and apparatus | |
US11129539B2 (en) | Pulse measuring device and control method thereof | |
JP2018507494A (en) | Feature extraction method and apparatus | |
CN111629659B (en) | Device and method for determining calibration timing of blood pressure measurement of electronic device | |
KR20180083593A (en) | Image processing method and electronic device implementing the same | |
EP3513715B1 (en) | Apparatus and method for determining calibration timing for blood pressure measurement in electronic device | |
US11361674B2 (en) | Encouraging speech system, encouraging speech method, and computer readable medium | |
CN109065145B (en) | Electrocardio data processing method and device and storage medium |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SAMSUNG ELECTRONICS CO., LTD., KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:PARK, SANG WOOK;KI, MYOUNG OH;HAN, YUN CHEOL;REEL/FRAME:034762/0387 Effective date: 20141007 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1551); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 4 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 8 |